May we count your visit with Google Analytics? It uses cookies and sends visit data to Google. You can change this any time under Cookie choices. Privacy

aquarium.guide
Choose your tank

Fish pages, lists, fit marks and tools use the tank you pick here.

Plan everything for this tank →
Menu
Home/Equipment/Buying guides

Air pumps by tank size

An air pump runs a sponge filter or an air stone; it doesn’t filter the water itself. Tetra rates each Whisper air pump for a tank size and publishes its air flow, so for each tank below: the smallest Whisper rated for it, and the next size up for a tall tank or a long air stone. No scores.

By tank sizeTwo sponge filtersFor power cutsSetting one up

The Whisper Tetra rates for your tank

Tetra Whisper air pumps by tank size, from Tetra’s own ratings and air flow
TankSmallest rated for itAir flowOne size up
5 gallon
Filters for 5 gallons		Whisper 100.5 L/min, one outletWhisper 20
1 L/min, one outlet
10 gallon
Filters for 10 gallons		Whisper 100.5 L/min, one outletWhisper 20
1 L/min, one outlet
20 gallon
Filters for 20 gallons		Whisper 201 L/min, one outletWhisper 40
1.3 L/min, one outlet
29 gallon
Filters for 29 gallons		Whisper 401.3 L/min, one outletWhisper 60
2.6 L/min, two outlets
40 gallon
Filters for 40 gallons		Whisper 401.3 L/min, one outletWhisper 60
2.6 L/min, two outlets
55 gallon
Filters for 55 gallons		Whisper 602.6 L/min, two outletsWhisper 100
3.3 L/min, two outlets
75 gallon
Filters for 75 gallons		Whisper 1003.3 L/min, two outletsWhisper AP 150
Not published
125 gallonWhisper AP 150Not publishedWhisper AP 300
Not published

Tetra gives the air flow at the outlet, not at the bottom of the tank. A pump pushes less air the deeper the outlet sits, so in a tall tank such as a 29 gallon, or with a long air stone, the next size up leaves air to spare; turn the extra down with a valve on the airline. Tetra says the Whisper line works in tanks up to 8 ft deep.

Running two sponge filters or stones

The Tetra Whisper 60 Air Pump and Tetra Whisper 100 Air Pump have two outlets, and Tetra’s air flow for them is both outlets together. The smaller Whispers have one: split it with a gang valve, which has a tap on each branch so you can balance the two, since a plain splitter doesn’t share air evenly.

For power cuts

A sponge filter stops when its pump does. Aquarium Co-Op’s single outlet and dual outlet battery pumps run from USB and switch to their own battery when the power goes out, so the sponge keeps the tank’s bacteria alive through an outage. Aquarium Co-Op gives its current pumps about 20 hours on a full charge, or 40 hours or more in power-save mode. The single-outlet pump moves 1.1 L/min, a little more than the Whisper 20; Co-Op gives its pumps no tank rating. Power outage plan.

Before you choose

Tetra’s page doesn’t list what comes in the box, so plan on airline tubing, a check valve and the sponge filter or air stone itself. Set the pump above the water line, or fit the check valve with its arrow toward the tank, so water can’t siphon back into the pump when the power goes off.

Aqueon rates its QuietFlow pumps by tank size too: the 10 for 2 to 10 gallon tanks, the 40 for tanks up to 40 gallons and the 100, with two outlets, for tanks up to 100 gallons. Each has a check valve built in, but Aqueon publishes no air flow, so they aren’t in the table above.

When an older Whisper’s bubbles weaken, it may not need replacing: Tetra sells repair kits for the Whisper 10 (item 77876-00), the 20 and 40 (77877-00) and the 60 and 100 (77878-01).

Setting up an air pump and sponge filter · Every air pump in the catalog · What it costs to run